DS1315N-33+

Overview

The DS1315N-33+ is a CMOS Phantom Time Chip combining a real-time clock and nonvolatile memory controller. It tracks hundredths of seconds, seconds, minutes, hours, day, date, month, and year with automatic leap year correction valid to 2100. Operating at +3.3V (3.0V to 3.6V range), it uses a serial bit stream for communication without requiring address space. The device supports battery backup for external SRAM via redundant battery inputs and features an industrial temperature range of -40°C to +85°C in a 16-pin PDIP package.

Feature Summary

• Phantom Clock Interface: Serial pattern recognition eliminates address space requirements for RTC communication.
• Nonvolatile Controller: Manages battery backup switching between VCC and BAT inputs to power external CMOS SRAM.
• Calendar Functions: Tracks time with BCD format and includes automatic leap year correction through 2100.
• Redundant Battery Support: Dual battery inputs (BAT1, BAT2) allow high-reliability applications with automatic voltage selection.

Applications

• Systems requiring nonvolatile timekeeping without dedicated bus interfaces.
• Applications needing battery-backed SRAM control alongside real-time clock functions.
• Industrial equipment operating within -40°C to +85°C temperature ranges.

Procurement Notes

Verify the 'N' suffix indicates the industrial temperature grade (-40°C to +85°C) and the '+ ' denotes lead-free/RoHS compliance. Confirm the 16-pin PDIP package matches the design footprint. Check current availability status as this component may be subject to limited supply or end-of-life conditions.

Selection Notes

Select the DS1315N-33+ when a 3.3V supply is required and the system utilizes a serial interface that can accommodate the 64-bit pattern recognition sequence. Ensure the external crystal has a 6pF load capacitance. Compare against the DS1315N-5+ if a 5V supply is preferred instead of 3.3V.

Part Context

This part belongs to the DS1315 family of Phantom Time Chips from Analog Devices/Maxim Integrated. The 'N' suffix specifies the industrial temperature range, while the '-33' indicates the 3.3V operating voltage variant. It shares the same pinout and functionality as other DS1315 variants but differs in supply voltage and temperature rating.

Replacement Considerations

The DS1315N-5+ serves as a direct replacement if the system operates at 5V instead of 3.3V. Other DS1315 variants with different packages (SO, TSSOP) require PCB layout changes. No direct digital equivalents with different interfaces are documented as substitutes.